hadoop NetgroupCache 源码

  • 2022-10-20
  • 浏览 (326)

haddop NetgroupCache 代码

文件路径:/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/NetgroupCache.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.hadoop.security;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;

import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;

/**
 * Class that caches the netgroups and inverts group-to-user map
 * to user-to-group map, primarily intended for use with
 * netgroups (as returned by getent netgrgoup) which only returns
 * group to user mapping.
 */
@InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce"})
@InterfaceStability.Unstable
public class NetgroupCache {
  private static ConcurrentHashMap<String, Set<String>> userToNetgroupsMap =
    new ConcurrentHashMap<String, Set<String>>();

  /**
   * Get netgroups for a given user
   *
   * @param user get groups for this user
   * @param groups put groups into this List
   */
  public static void getNetgroups(final String user,
      List<String> groups) {
    Set<String> userGroups = userToNetgroupsMap.get(user);
    //ConcurrentHashMap does not allow null values; 
    //So null value check can be used to check if the key exists
    if (userGroups != null) {
      groups.addAll(userGroups);
    }
  }

  /**
   * Get the list of cached netgroups
   *
   * @return list of cached groups
   */
  public static List<String> getNetgroupNames() {
    return new ArrayList<>(getGroups());
  }

  private static Set<String> getGroups() {
    Set<String> allGroups = new HashSet<>();
    for (Set<String> userGroups : userToNetgroupsMap.values()) {
      allGroups.addAll(userGroups);
    }
    return allGroups;
  }

  /**
   * Returns true if a given netgroup is cached
   *
   * @param group check if this group is cached
   * @return true if group is cached, false otherwise
   */
  public static boolean isCached(String group) {
    return getGroups().contains(group);
  }

  /**
   * Clear the cache
   */
  public static void clear() {
    userToNetgroupsMap.clear();
  }

  /**
   * Add group to cache
   *
   * @param group name of the group to add to cache
   * @param users list of users for a given group
   */
  public static void add(String group, List<String> users) {
    for (String user : users) {
      Set<String> userGroups = userToNetgroupsMap.get(user);
      // ConcurrentHashMap does not allow null values; 
      // So null value check can be used to check if the key exists
      if (userGroups == null) {
        //Generate a ConcurrentHashSet (backed by the keyset of the ConcurrentHashMap)
        userGroups =
            Collections.newSetFromMap(new ConcurrentHashMap<String,Boolean>());
        Set<String> currentSet = userToNetgroupsMap.putIfAbsent(user, userGroups);
        if (currentSet != null) {
          userGroups = currentSet;
        }
      }
      userGroups.add(group);
    }
  }
}

相关信息

hadoop 源码目录

相关文章

hadoop AccessControlException 源码

hadoop AnnotatedSecurityInfo 源码

hadoop AuthenticationFilterInitializer 源码

hadoop CompositeGroupsMapping 源码

hadoop Credentials 源码

hadoop FastSaslClientFactory 源码

hadoop FastSaslServerFactory 源码

hadoop GroupMappingServiceProvider 源码

hadoop Groups 源码

hadoop HadoopKerberosName 源码

0  赞